Basic amino acid salts of chloramphenicol succinate

ABSTRACT

The basic amino acid salts of chloramphenicol succinate cause little or no pain when administered intramuscularly to human beings.

United States Patent Yoshitaka Ikezuki; Sadayoshi Fujimori; Kawashima Yuji; Yoshihisa Nozaki, all of Tokyo, Japan [72] Inventors 21 1 Appl. No. 756,547

[22] Filed Aug. 30, 1968 [45] Patented Sept. 21, I971 73 Assignee Yamanouchi Pharmaceutical Co., Ltd.

Tokyo, Japan [32] Priority Aug. 3], 1967 [33] Japan [54] BASIC AMINO ACID SALTS OF CHLORAMPIIENICOL SUCCINATE 1 Claim, 1 Drawing Fig.

[52] US. Cl 260/485 G, 424/313 [51] Int. Cl A6lk 27/00, C07c 69/40, C070 103/40 [50] Field of Search 260/485 G [56] References Cited OTHER REFERENCES Wilson et al., Textbook of Organic Medicinal and Pharmaceutical Chemistry, 5th Ed., pp. 338- 340,'( 1966) Primary Examiner-Lewis Gotts Assistant Examiner-E. .I. Skelly Attorney-Wenderoth, Lind & Ponack PATENIEDsmuan 3.607.911

II I III I400 I200 I000 800 600 YOSHITAKI IKEIUKI,

SADAYOSIII FIIIIMORI. T YIJJI KAWASIIIMII an INVENTORS Byldmlufl. Zuv mw ATTORNEYS o vosmmsn Romp -Y .j

BASIC AMINO ACID SALTS F CHLORAMPHENICOL SUCCINATE This invention relates to salts of chloramphenicol succinate with basic amino acids. It further relates to the use of the basic The following is a report of the tests concerning pain produced by the intramuscular administration of the basic amino acid salts of chloramphenicol succinate of this invention, and their results.

amino acid salts of chloramphenicol by intramuscular injec- 5 tion with little or no pain when administered to human beings. TEST 1 It is known that chloramphenicol itself in the form of suspension can be used for an intramuscular injection which The degree of P caused y the intramuscular administradoes not cause much pain and which maintains a prolonged of chloramphenicol Succihate in dogs has been deterblood level. However, the suspension has the disadvantage l0 'h by the Various degrees of behavior Patterns sllch as that it does not show a rise into a high blood level in'a short barking, attempts bite, and the turning of the head! All i hi h meansimmediate eff t) aqueous solution of each of sodium salt of chloramphenicol On the other hand, the sodium salt of chloramphenicol sucsuccmale, hereafte, referred to as arglhlhe Salt of cinate is widely used for intravenousinjections because it chloramphemcol succinale, hereafter referred) as E readily dissolves in water and because after it is administered; lysine of chloramphenicol succlhate, and ol'nhhlne of i i decomposes so that the Mood l l f the chloramphenicol succinate; each having the concentration of hl h i l rises i kl v v 250 mg./ml., was intramusculariy injected into the femoral This sodium salt of chloramphenicol succinate cannot be muscle of the hlhdhmb f 10 mongrel male'dogshf average used for intramuscular injections because it-causes violent" y of at the rate of 50 P kilogram of pain which, even when local anesthetics are added to the in- 0 y AS a blank, @Physiological Saline Solution was jection solution, cannot be sufficiently reduced. This renders used: The results of the test are shown in Table the use of the sodium salt of chloramphenicol succinate immficahce'of h marks t, +1 in the table is as f practical for intramuscular injections. Moreover, there are. lows: W also dangers such'as unexpectedly causing shock in hypersen- "P reglstef y Pa sitive patiemg i :reaction to pain unclear TABLE 1 I Lysine salt of Ornithine salt oi Physiological chloramphenicol chloramphenicol saline (blank) CPS-Na CPS-Arg succinate succinatc During Alter During atter During Atter During Alter During After Number of inieeinjecmjecmjecmieeinjecinjeeinieeinjecinjecanimals tion tion tion tion tion tiontion tion tion tion :t: i a: a; 1 a: :l: :l: :l:

it has now been found that the salt of chloramphenicol suc showed slight reaction to pain cinate with a basic amino acid selected from the group consist- -llshowed obvious reaction to pain ing of arginine, lysine and ornithine is not only easily dissolved +H- I showedviolent reaction to pain in water, but when administered intramuscularly, causes little or no pain As is manifest from the above Table l, the dogs to which A basic amino acid salt of chloramphenicol succinate of this- CPS'Na a admlhlstercfd" mtramuscularlx heglsytered "lolcm invention can be prepared by mixinga solution or asuspenand/0' Obvlous h Elmer h mlecno" when Sion of chloramphenicoj Succinate with a solution of a the compounds according to this invention were administered stoichiometric quantity of the corresponding. basic amino z l h h dogs reglstered or no Pam durmg acid. As solvents, water and/or alcohol can be employed. an a ter t e mjecuon The basic amino acid salt of chloramphenicol succinate can- TEST 2 be isolated by either evaporating the solvent ina vacuum or by adding an organic solvent in which the salt'is at the mostonly lnjectionsof CPS-Na .whichcontained various types of local slightly dissolved, and then filtering the precipitated salt. anesthetics and an injection of CPS-Arg were administered in- The basic amino acid salt of chloramphenicol succinate can tramuscularly to human beings and their reactions were tested be prepared as dry solid medicament for*injection use by disand recorded. 4.ml. of an aqueous solutionof L49 g. of CPS solving it in distilled water and then filtering it with abactcrial Na and 1.85 gr of-CBS-Arg (each corrcsponding to l.() g. of filter and then freeze-drying it. The amountol' the basic amino chloramphenicol) were injected intramuscularly into the acid salt of chloramphenicol succinatc to be administered to upper part oi'thc arms'oi'human subjects and the pain they rchuman beings can be calculated according to the data of thc gistcrcd during and alter the injection is summarized in Table US. Pharmacopcia XVII, page I I7. 2.

'lAlHil) 2 Nnmlmr oi patients 'lypo oi anaesthetic usod tested l'rolw. and the quantity Observations o (Ji'il'NaU Administration was-stopped :ti'tvr (1.2-0.4 llll. ot injvi-tion ln-l'nusi' of violent pain. i Sumo, 2-hutoxy-N-(2-diothyiaininootliyl)oin- Administration.was stopped after (L-"rinl. oi llljN'llUll lint-austoi choninainido hydrochloride, 0.6%. violent pain. l .do llonzyl alcohol, 2.0%. lativnt registered pain attiino of injection and pain im-n-nsvd :ii'it-r i5 ininnt si-i sation at linger tips wns lost. I .do l-mothyl-N-2,li-pipnooloxylididi: l'ntiont rvg s i-rc lpnin itt-tinio oi injt-ction; tnrnvd I'ill in color-at hydrochloride, 1.0%. point. of injection; pain grow worsm 1 t ..do c N-diothylaminoacoto-2,tl-xylidido Patient rogistorod much pain at time oi injection; after I hour,

hydrochloride, 0.5%. sensation-oi injected arm lost; pain porsisti-d. 1 .do .do lntiunt registered much pain at time 01 injection; after 30 minutes,

hives-litre red rash appeared on neck and chest. 2 .do 2-rnethyl-2-propylaminopropyl benzoato Administration was stopped-alter 1-1.3 ml. of injection because of hydrochloride, 0.5%. violent pain. 6 ClS-Arg Registered no pain at time of injection and even 24 hours later.

6 Physiological saline .1 Do

TEST 3 Concerning the length of time pain persisted when injection of CPS-Na (contained local anaesthetic) and injection of CPS- Arg were injected into human beings:

Ten healthy volunteers were separated into two equal groups. To one group 5 ml. of an aqueous solution of 1.85 g. of CPS-Arg (corresponding to 1.0 g. of chloramphenicol) was administered intramuscularly and to the other, 5 ml. of an aqueous solution of 1.49 g. of CPS-Na (corresponding to 1.0

of chloramphenicol) which contained N- diethylaminoaceto-2, 6-xylidide in the deltoid muscle of the upper arm, and the degree of pain was compared. The results are shown in Table 3.

TABLE 3 creat CPS-Na (s'volun- (5 volun- Observations Probe teers) teers) 1. Little or no pain registered- 1 2. Some but insignificant pain 4 1 After probe registered.

was admin- 3. Strong but bearable pain 0 2 istered. registered.

4. Violent pain registered; 0 2

patient asked never to be given injection again.

Time when 1. At time of administration. 0 5 pain 2. Right alter administration... '1 0 appeared. 3. 5-7 min. alter administration. *4 0 1. At time of administration. 0 0

Length of 2. 0-10 minutes 0 3 time pain 3. -20 minutes *1 0 persisted. 4. 20-30 minutes *2 1 5. 30-60 minutes 1 1 Registered slight pain.

As can be seen from the results of Tables 2 and 3, CPS-Na causes violent pain at the time of intramuscular administration and after. Even when a local anesthetic is added, the painat the time of administration remained quite violent. On the other hand, when a salt of this invention (for example, CPS- Arg) is used, the subjects register little or no pain at the time of intramuscular injection or afterwards even when local anesthetics are not used. The degree of pain registered when a contrast of a physiological saline solution was used was about the same.

The accompanying figure of drawing is the infrared spectrum of CPS-Arg which was prepared by Example 1.

1. This spectrum shows no absorption of -COOH group at over 1700, 1250 and 920 2. This spectrum shows the absorption of COO'group at 1600 and 1400""- EXAMPLE l 13.1 g. of chloramphenicol succinate (hereinafter abbreviated as CPS) were suspended in 13 ml. of water, and then 5.3 g. of L-arginine free base were gradually added into the resulting suspension while stirring. The mixture became a clear pale yellow in color when it was stirred continuously for 5 minutes. By gradually adding 500 ml. of dioxane to the reaction mixture, crystals of CPS-L-arginine were precipitated. The crystals were then filtered and washed with a small amount of dioxane and dried. Yield: 14.7 g. Melting point: 145 C. (decomp.) [a =+8.6:t0.5 (C 10.0 water) Elementary analysis as C H N O Ch:

The infrared spectrum of the object of this example is as per the accompanying figure of drawing.

EXAMPLE 2 EXAMPLE 3 130.9 g. of CPS were suspended into 250 ml. of distilled water for injection and while stirring, 53.8 g. of Larginine free base was added. Distilled water for injection was added to the solution until its volume was 400 ml. and it was then filtered in a bacterial filter and then aseptically divided into vials of 4 ml. and freeze-dried. Each vial contained 1.85 g. of CPSL-arg (1.0 g. of chloramphenicol). The infrared spectrum of the object of this example was the same as that of Example 1.

EXAMPLE 5 15 ml. of water were added into 12.7 g. of CPS and to this solution was added a water solution of basic L-ornithine which was prepared by passing the water solution of 5.1 g. of L-ornithine hydrochloride through an ion exchange resin (OH type). The thus-obtained clear reaction mixture was treated in the same manner as in Example 1 and CPS-L-ornithine was obtained. Yield, 10.0 g. Melting point of crystals which are recrystallized from a mixture of n-butanol and water (volume ratio 100:1): 112-114C.

EXAMPLE 6 1.74 g. of L-arginine was gradually added while stirring into a solution of 4.23 g. of chloramphenicol succinate in ml. of ethanol. Upon completion of the addition, the system was stirred further for some time, whereby the L-arginine was dissolved, and soon needlelike crystals precipitated. Then after stirring for 1 hour, the crystals were filtered and washed with cold ethanol and thus CPS-L-arginine was obtained. Yield: 5.5 g. Melting point: 145 C. (decomp.). The product is already sufficie'ntly pure but if necessary it can be recrystallized from a mixture of ethanol: methanol (volume ratio 8:2).

EXAMPLE 7 365 mg. of CPS was dissolved in 10 ml. of ethanol and the solution was added into a solution of 1 13.8 mg. of L-ornithine in ethanol, whereby the solution became slightly cloudy. When a mixture of ethyl acetate and ether (volume ratio 2:1) was added, the solution became cloudier. CPS-L-ornithine precipitates when the solution is cooled. The precipitate is filtered and washed with a mixture of ethyl acetate and ether and dried. Yield: 363 mg. Melting point of crystals which are recrystallized from a mixture of n-butanol and water (volume ratio 100:1) 112-1 14 C. Elementary analysis as C H O, N,,Cl

C(% (1' N(% C(%) H(%) N(%) Calculated 43.25 5.08 10.09 Calculated 44.29 5.3l 9.81 Found 43.24 s.4| 9.19 Found 43.96 5.61 9.81

EXAM LE 8 I P The salts according to this invention-which In the system 0 mgo L-lysin ere sol ed n 4 mlof Water and 53 effectively act as the free chloramphenicol itself-are used for mg. of chloramphcnicol succinate were added to the resultant th purposes for which chloramphenicol is employed and in solution. The thus-obtained clear reaction mixture was freeze- 10 ou t orre nding to the dosages in which the latter is dried used in human and in veterinary medicines. As aforeindicated,

lhc Product was diSSOh/cd in 1 of methanol, after the pain usually associated with prior intramuscular adminiswhich a mixture of ethyl acetate and ether (volume ratio of (ration i i mv t d. 2:1) was added, while stirring, thus obtaining CPS-L-lysine. Wh ti claimed is: Then it Was filtered nd W h wi h a miX fB ofet y acetate 1. A salt of chloramphenicol succinate with a basic amino and ether and Yield: 534 8- Memng P0int l acid selected from the group consisting of L-arginine, L-lysine C. Elementary analysis as c n up cu; d L-ornithine. 

